NATE Fisher’s unexpected death on “Six Feet Under” a few weeks back was this summer’s most-talked-about TV moment – that almost didn’t happen.

“There was a lot of resistance in the writers’ room to Nate dying,” series creator Alan Ball said yesterday. “But I couldn’t find any other way to get as organic and real.”

Ball, on a conference call to discuss this Sunday’s series finale and the series in general, said he felt compelled to kill off the self-absorbed Nate (Peter Krause), who died after cheating on wife Brenda (Rachel Griffiths) with step-sister Maggie (Tina Holmes).

“Everybody [in the writers’ room] said it just felt so sad and I said, ‘Great, give me something else, if we find something better we’ll do it,’ ” Ball said.

“But nothing else clicked the way [Nate’s death] did for me,” Ball said. “This is a show about death and its place in our lives, and Nate’s character – his overall series arc – had been inching toward full acceptance of his mortality.

“I felt like it needed to be him,” Ball said. “Even though it’s an ensemble drama, Nate had always been the central character, at least in the beginning.”

Asked about the possibility of another season, Ball said this is it for the funeral-home drama.

“It was my decision to end the show, partially because I wanted to move on . . . I’d spent so much of my life contemplating mortality and peering into the abyss,” Ball said.

“I wanted to leave at the end of season four but they said, no, you can’t end it,” Ball said. “They had a hard time finding someone else to take it on.

“So I said, OK . . . but this has to be the last season. Don’t even talk to me about another season.

Ball described the saga of the Fishers – Claire, David, Nate, Ruth – and the other “Six Feet” characters as “a novel” spread out over five seasons.

“We love these characters no matter what they do,” he said. “One of the motivations for us . . . was to constantly reveal sides of these characters we hadn’t seen before, hopefully in ways that were organic.

“For me, the most satisfying aspect [of the show] was taking the journey with the characters,” he said. “I didn’t want to create a world of heroes and villains but of infinite complexity . . . to create a rich and complicated show that I myself would watch.

“I wanted to see people live authentic lives in an increasingly unauthentic universe – and to explore things you don’t see that much.”